Sean: Something nice in aluminum or on the entry level side of carbon. 20 speed Ultegra or equal or better. Just something to train on and maybe do a triathlon or two. If I were paying cash I'd be looking at the $1,000-$1,500 range for a Craigslist special. I'm 5'10ish, 30" inseam.
Chris: The 06-up R6 is just a very malleable bike. Same with the new R1. It makes for a really great handling and riding bike but makes it easier to bend stuff in crashes. The 05 and earlier bikes were made a bit more rigid and don't bend in minor crashes.